Problems with Abit VA-20 - minus voltages plus others?

Discussion in 'Abit' started by ohaya, Mar 27, 2005.

  1. ohaya

    ohaya Guest

    Hi,

    I have a new VA-20, and am running SpeedFan to monitor the system. I
    noticed that SpeedFan is reporting the -12V as being something like
    -16V.
    Unfortunately the BIOS doesn't show the minus voltages, so I can't
    confirm if this is right or if SpeedFan isn't detecting the voltage
    correctly. The SpeedFan author notes on his web page that these
    voltages can sometimes be incorrectly reported.

    If anyone else out there has a VA-20 and is either running SpeedFan or
    gotten MBM to work with this motherboard, can you post back what your
    minus voltages are showing as?

    The reason that I'm looking into this is that I've been trying to track
    down a high-pitched whistling sound that I've traced back to the VA-20
    itself, and am trying to figure out why this is happening. The sound
    occurs after the system has been on for awhile.

    Thanks,
    Jim
     
    ohaya, Mar 27, 2005
    #1
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  2. ohaya

    JefN Guest

    | Hi,
    |
    | I have a new VA-20, and am running SpeedFan to monitor the system. I
    | noticed that SpeedFan is reporting the -12V as being something like
    | -16V.
    | Unfortunately the BIOS doesn't show the minus voltages, so I can't
    | confirm if this is right or if SpeedFan isn't detecting the voltage
    | correctly. The SpeedFan author notes on his web page that these
    | voltages can sometimes be incorrectly reported.
    |
    | If anyone else out there has a VA-20 and is either running SpeedFan or
    | gotten MBM to work with this motherboard, can you post back what your
    | minus voltages are showing as?
    |
    | The reason that I'm looking into this is that I've been trying to track
    | down a high-pitched whistling sound that I've traced back to the VA-20
    | itself, and am trying to figure out why this is happening. The sound
    | occurs after the system has been on for awhile.
    |
    | Thanks,
    | Jim


    Hi Jim -

    The -5v and -12v rails are legacy and are no longer used on any commonly
    available hardware. Even serial ports, which rely on a negative voltage for
    their handshaking, generate their own negative via hardware on the
    motherboard.

    Because there's absolutely no load on the negative rails you often will get
    wacky readings as a result.

    Cannot comment directly on your high-pitched whistling other than open up
    the case and give a close ear to the system. Could be that you've a fan
    that's starting to go south.

    Jef
     
    JefN, Mar 27, 2005
    #2
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  3. As Jef says, the -5 and -12 lines aren't used nowadays. In fact, on quite a
    few Abit boards over the last few years, Abit has re-used them to represent
    other voltages. This may well explain why your readings bear no relation to
    what they "should" be. Try using the monitoring utility included with the
    board to see if it shows any other readings (AGP and/or bus Vtt for
    example).

    The whistling is an odd one. Do you actually hear it through the speakers,
    or is it something coming out of the case???
    --


    Richard Hopkins
    Cardiff, Wales, United Kingdom
    (replace nospam with pipex in reply address)

    The UK's leading technology reseller www.dabs.com
     
    Richard Hopkins, Mar 27, 2005
    #3
  4. ohaya

    ohaya Guest


    Jef,

    Thanks for the info re. -12V. FYI, for confirmation, I swapped in a
    completely different power supply (different manufacturer and model),
    and SpeedFan is showing the same thing, -16V on the -12V sensor.

    Re. the whistling, I've had a thread on alt.comp.hardware.homebuilt
    where I described all of the things that I've done to diagnose this
    problem. The sound does seem to be coming from the power section of the
    motherboard itself.

    I was starting to wonder if maybe the minus voltages might be causing
    the coil or caps to "sing", but now that I've swapped in a different
    power supply and am seeing the same minus voltages, I think I've
    eliminated that as a possibility.

    Thanks again,
    Jim
     
    ohaya, Mar 27, 2005
    #4
  5. Hi Jim! I too have this singing va-20 and I can't make it stop.
    In my case it stops if I run [email protected] This is a numbercruncher that
    really loads the cpu. But if I turn off the program the sound comes
    back. So I don't think the powersupply is the bad guy.
    Another stopper is if I take out the graphicscard and use the
    unichrome instead.
    I would like to try one of those coolingsprays with a thin tube so I
    can test different components on the mobo.
    In a way i'm better off than you because mine keeps sounding with open
    case. If I find something useful I get back.

    Anders


    --
     
    Anders Henningsson, Mar 27, 2005
    #5
  6. ohaya

    ohaya Guest


    Anders,

    Thanks for your post. At one point, I'd almost thought that I was
    imagining it, except for the fact that I took one of those small voice
    recorders, and recorded the sound. I'm trying to figure out how to
    transfer to a sound file so I can post it on the web somewhere. If I
    figure that one out, I'll post back with a link.

    Actually now, once it starts, it'll sometimes continue even after I open
    the case.

    I tried for several days to figure out exactly where the sound was
    coming from on the motherboard (I know it's from there because I
    unplugged everything, including the CPU fan, and it was still there.).

    I just pulled everything out of the case this afternoon, and have the
    power supply and motherboard sitting on my table, and have been running
    CPU Burnin, trying to get the sound to appear, but predictably, I can't
    get it to happen.

    In my case, I don't have a graphics card, I'm just using the onboard
    video, and I'm getting the sound. Once I get the sound, it's there
    regardless of what I'm running on the system.

    I appreciate it if you post back if you find something, and I'll
    obviously do the same, though I'm getting close to returning the board.
    I'd really hate to do that, because spec-wise, it is almost perfect for
    what I'm building it for :(...

    Jim
     
    ohaya, Mar 28, 2005
    #6
  7. ohaya

    ohaya Guest


    Richard,

    I get the sound with EVERYTHING disconnected (with basically only the
    power supply connected to the motherboard). I get the sound even when
    the CPU fan is unplugged. I've pulled the power supply out of the case
    to separate it, so I'm also sure the sound is coming from the
    motherboard itself and not from the power supply.

    I just pulled everything (including the motherboard and the power
    supply) out of the case this afternoon, and have been trying to get it
    to produce the sound, but so far no luck.

    I'm starting to wonder if maybe the motherboard is actually resonating
    inside the case, but I don't think so, because if I press on the
    motherboard while I have the sound, the sound remains unaltered.

    Jim
     
    ohaya, Mar 28, 2005
    #7
  8. ohaya

    - HAL9000 Guest

    The inductors close to the cpu should be your "birds", LOL. If you
    squeeze them they should de-tune slightly.

    Forrest

    Motherboard Help By HAL web site:
    http://home.comcast.net/~mobo.help/



    < snip >
     
    - HAL9000, Mar 28, 2005
    #8
  9. ohaya

    ohaya Guest


    Forrest,

    After running the motherboard outside the case, I was finally able to
    get some sound from it. It was much, much lower in volume than when the
    board was in the case (I'm guessing that when the board is in the case,
    the case is amplifying the sound).

    I did some "sleuthing", basically trying to block off different parts of
    the board to try to isolate the sound.

    I know that the coils are prime candidates, but I've squeezed and tapped
    and poked at the coils on the board, with no effect.

    After a lot more listening (with the board outside the case and with the
    CPU fan off sometimes), it appears that the sound is coming from the
    area of the CPU or the CPU socket (there are some components under the
    "ledge" of the CPU socket). I did some searching on the net using
    Google Groups, and I ran across a post that mentioned a thread on
    hardwareanalysis.com, where a number of people were reporting that they
    were "hearing their CPU". I don't know if it is, in fact, possible for
    a CPU to "sing", but I'm just posting what I found. In my case, it does
    appear to me that the sound is emanating from the CPU itself or one or
    more of the components that are surface-mounted under the edge of the
    CPU socket.

    Jim
     
    ohaya, Mar 28, 2005
    #9
  10. ohaya

    - HAL9000 Guest

    Are you able to change the bird song, LOL, when you press on one of
    the surface mount components (or cpu) ?

    Forrest

    Motherboard Help By HAL web site:
    http://home.comcast.net/~mobo.help/
     
    - HAL9000, Mar 29, 2005
    #10
  11. ohaya

    ohaya Guest


    Hi,

    No, the sound didn't change, at least not on the components that I
    touched, which was just about everything on the motherboard. I did the
    same with the CPU, though the heatsink was mounted on top of it, but
    again, no change in the sound.

    Jim
     
    ohaya, Mar 30, 2005
    #11
  12. ohaya

    - HAL9000 Guest

    Oops, can't find out which it is... I was going to suggest putting a
    drop of super glue on the affected component. I've never heard of
    anything but an inductor (or something with an inductor inside it)
    sing.

    Forrest

    Motherboard Help By HAL web site:
    http://home.comcast.net/~mobo.help/
     
    - HAL9000, Mar 30, 2005
    #12
  13. ohaya

    ohaya Guest

    Hi,

    Yes, I know. Believe me, neither have I, but here's a thread on another
    forum that talks about similar problems:

    http://www.hardforum.com/showthread.php?t=818291

    Jim
     
    ohaya, Mar 30, 2005
    #13
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